Selective overcoat

ABSTRACT

Examples described herein include examples methods for generating varnish knockouts that include applying a fixer material to a surface of a print medium, selectively applying a print material over the fixer material to form an image, and applying an overcoat material to form a durable coating on areas over the image and a nondurable coating over other areas of the surface.

BACKGROUND

It is possible to print on many different types of print media. Forexample, print systems exist to print on paper, plastics, card stock,corrugated cardboard and other media. Once the media is printed it canbe further processed to create specific objects. In some scenarios, theprinted media, such as a printed corrugated cardboard, can be folded,creased, cut, or scored to create boxes or display structures. Toprotect the printed image on such print media during the additionalprocessing, some printing systems applying an overcoat material tocreate a durable coating over the printed image to resist scratching,smearing, or other degradations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a schematic representation of an example printing system.

FIG. 2 depicts another schematic representation of the example printingsystem.

FIG. 3 depicts a schematic representation of a fixer application stagein an example printing process.

FIG. 4 depicts a schematic representation of a printing materialapplication stage in the example printing process.

FIG. 5 depicts a schematic representation of an overcoat applicationstage in the example printing process.

FIG. 6 depicts a schematic representation of a cleaning stage in theexample printing process.

FIG. 7 is a flowchart of an example method for creating overcoatknockout regions using a fixer material.

DETAILED DESCRIPTION

In various use cases, printed low-grade or commodity quality printmedia, such as card stock or corrugated cardboard, are used to formboxes, packaging, display installations, and the like. In suchscenarios, the printed media is first printed while it is still in arelatively flat condition. The sheets of the print media are thenstacked for later processing or fed directly into other finishingdevices. For example, the printed media can be further processed usingvarious cutting, folding, scoring, gluing, printing, or cutting devicesto process the printed media into the end product (e.g., a retail box,retail display case, serialized shipping cartons, etc.).

The stacking and/or further processing of the printed media can oftencause smudges, scratches or other degradations to the printed images. Toavoid such damage to the printed image, many printing systems apply anovercoat material, such as a varnish, to form a durable coating on topof the printing material used to generate the printed image. However,the same properties of the overcoat material that aid in preventingdamage to the printed image can also cause complications when trying toprint or apply adhesives to the surface of the print media during theadditional processing. For example, in some instances a manufacturer ofboxes may wish to cut, fold, or otherwise include the printed printmedia into a box and print a tracking number or serial number on thatbox. In such cases, the overcoat material on the printed surface of theprint media can prevent the adhesive from forming a durable bond and/ordurably accept the printing material.

To provide for regions on the printed surface of the print media onwhich adhesive or subsequent printing material can be durably applied,implementations of the present disclosure include systems, devices, andmethods for generating varnish knockout regions using a correspondingdurable coating inhibiting fixer material. In some implementations, thefixer material can also aid in the fixation of the printing material tothe print media to generate high-quality and vibrant printed images.Accordingly, in various implementations, the fixer material used to bothto aid in the generation of high-quality printed images can also beformulated to prevent the overcoat material from forming a durablecoating in specific regions on the surface of the printed print medium.In the regions where the overcoat material is inhibited from forming adurable coating, the overcoat material can be removed to provideprintable or bondable regions in which printing material and/or adhesivecan be applied.

FIG. 1 depicts a schematic representation of an example printing system100 according to various implementations of the present disclosure. Asshown, the example printing system 100 can include a controller 110coupled to a fixer applicator 101, a print engine 102, an overcoatapplicator 103, and a conditioner/cleaner 104. In some implementations,as in the example shown, the printing system 100 may also include amedia handler 105 coupled to the controller 110. In any suchimplementation, the controller 110 can include a non-transitory computerreadable medium 111 on which can be stored executable code forcontrolling the fixer applicator 101, the print engine 102, the overcoatapplicator 103, the conditioner/cleaner 104, an/or the media handler105. Accordingly, the controller 110, such as a processor, amicrocontroller, or any other combination of hardware and/or executablecode, can execute the executable code 112 stored on the non-transitorycomputer readable medium 111 to control the various components of theexample printing system 100 to execute the corresponding operations toimplement the functionality of the system as a whole and the individualcomponents described herein.

FIG. 2 shows another depiction of the example printing system 100. Inthe specific depiction shown, the media handler 105 includes a conveyorbelt type conveyance for moving sheet or web type print material in thedirection indicated by arrow 10 for presentation to the fixer applicator101, the print engine 102, the overcoat applicator 103, and theconditioner/cleaner 104. While a conveyor belt type media handler 105 isdepicted, other types of media handlers are possible. In the specificexample depicted in FIG. 2 the print media 115 is depicted as a sheettype print media (e.g., a sheet of corrugated cardboard or card stock).

In such implementations, the print media 115 can be moved along thedirection indicated by arrow 10 by the media handler 105 to be presentedfirst to the fixer applicator 101. In various implementations of thedisclosure, the fixer applicator 101 can include any type of analogand/or digital application mechanism for applying a layer or coating offixer material. For example, the fixer applicator 101 can include aliquid applicator, such as a roller, a brush, a sprayer, a digitallycontrolled jet system, a flexographic printing plate, and the like.

As the media handler 105 moves the print media 115 past the fixerapplicator 101, a fixer material can be applied to any or all regions ofthe surface of the print media 115. The print engine 102 can thenselectively apply various monochromatic or polychromatic printingmaterials on top of the regions of the fixer material applied by thefixer applicator 101. Accordingly, the print engine 102 can print on orotherwise apply printing material to sub regions of the regions of theprint media 115 on which fixer material has been applied. Inimplementations of the present disclosure, the print engine 102 caninclude any combination of printing elements. For example, the printengine 102 can include various types of inkjet print heads,electrophotographic printing elements, or any other type of digital andanalog printing technologies.

The fixer material can include any type of liquid, semiliquid, or gelhaving a physical, chemical, or other material properties that caninteract with an/or react to printing material applied by the printengine 102 and/or the overcoat applicator 103. For instance, the fixermaterial applied by the fixer applicator 101 can include any of varioustypes of salt solutions. Such salt solutions can be formulated with aparticular saline concentration so as to cause the small particles ofpigments in the printing material applied by the print engine 102 toform larger particles of pigments. The formation of larger particles ofpigments helps prevent the pigments from being absorbed or penetratingpast the surface of the print media 115. As such, the larger particlestend to stay on the surface of the print media 115 to produce moresaturated and vibrant printed images.

To protect the printed image on the print media 115, the print media 115can be moved by the media handler 105 to be presented to the overcoatapplicator 103. The overcoat applicator 103 can apply a layer ofovercoat material on top of the printing material and the fixer materialpreviously applied to the print media 115. As described herein, thefixer material applied by the fixer applicator 101 can interact with theovercoat material applied by the overcoat applicator 103 in regionswhere the two materials are not separated by an intermediate applicationof printing material applied by the print engine 102.

In various implementations of the present disclosure, the overcoatmaterial can include various types of varnishes. Such varnishes can havespecific physical, chemical, and/or material properties which in thepresence of the fixer material will not dry or cure into a durablecoating. For example, the varnishes can be water-soluble or salinephobic such that it interacts with a salt based fixer material. Invarious implementations, in the regions of the print media 115 in whichthe fixer material and the overcoat material are in contact with oneanother, the two interact with one another to prevent the overcoatmaterial from forming a durable coating in those regions. In contrast,the regions in which the overcoat material is in contact with theprinting material, the overcoat material can dry and/or cure to form adurable protective coating over the printed regions of the print media115. The interaction between the overcoat material and the fixermaterial can cause the overcoat material, such as a varnish, to dry intoa nondurable or powdery layer which can be easily removed with brushesand/or bursts of air or other gas.

In some implementations, the conditioner/cleaner 104 can includecomponents for conditioning and/or cleaning the nondurable layers ofovercoat materials and fixer materials in the regions in which the twomaterials are in contact with one another. For example, theconditioner/cleaner 104 can include heaters/dryers for drying or curingthe overcoat material. The regions in which the overcoat material doesnot form a durable coating, the conditioner/cleaner 104 can also includevarious cleaning elements, such as air nozzles, brushes, rollers, andthe like, for removing the nondurable regions of overcoat materialand/or fixer material. In this way, the regions in which the fixermaterial and the overcoat material are in contact with one another canbe taken down to the bare surface of the print media 115 such that it isaccessible for additional printing and/or gluing in further processingof the print media 115.

FIGS. 3 through 6 depicts the various stages of a printing processaccording to implementations of the present disclosure. In particular,FIGS. 3 through 6 depicts the treatment of the print media 115 by thevarious components of the example printing system 100 in the variouscorresponding stages of the printing process.

FIG. 3 illustrates the application of the fixer material by the fixerapplicator 101 to the print media 115 as it moves in the directionindicated by arrow 10. In FIG. 3, the print media 115 is depicted aspartially treated with the fixer material being applied by the fixerapplicator 101. The region 203 represents the region of the print media115 on which the fixer material has been applied, while the region 201depicts the region of the print media 115 that is still untreated by thefixer applicator 101. Once the surface of the print media 115 is coatedwith the fixer material, it can be fed or otherwise passed to the printengine 100 to, as depicted in FIG. 4.

As shown in FIG. 4, the print medium 115 is coated first with the fixermaterial on which the print engine 102 can selectively apply printingmaterial to the regions 215. As the print medium 115 moves the directionindicated by arrow 10, the region 205 of the print medium 115 includesprinted regions 215 and under printed regions 220. The printed regions215 can include any type of printed image that includes one or morecolors of printing material that includes corresponding coloredpigments. As shown, the unprinted regions 220 can be disposed aroundand/or disposed within printed regions of 215. For the sake of clarity,the regions 220 represent regions in which the surface of the printmedium 115 is only treated with the fixer material, and the regions 215represent regions in which printing material is applied on top of thefixer material. Once the print engine 102 has completed applyingprinting material on top of the fixer material to generate correspondingprinted images, the print medium 115 treated now with the fixer materialand printing material can be passed to or otherwise presented to theovercoat applicator 103, as depicted in FIG. 5.

As shown in FIG. 5, the overcoat applicator to apply an overcoatmaterial, such as a varnish, on top of the regions 215 and 220 of theprint medium 115. In such implementations, the overcoat applicator 103can include any type of digital or analog coating mechanism for applyingthe fluid overcoat material. In the particular stage depicted in FIG. 5of applying the overcoat material, the region 205 represents the regionof the print medium 115 which is been coated only with the fixermaterial and printing material, while the region 207 represents theregion of the print medium on which the overcoat material has beencoated on top of the regions 215 and 220.

With the overcoat material applied on top of the printing material andthe fixer material, the print medium 115 can be moved along thedirection indicated by arrow 10 to be passed to or otherwise resented tothe conditioner/cleaner 104. In various implementations, theconditioner/cleaner 104 can dry or otherwise cure the overcoat materialto generate durable coatings in regions 215 and nondurable layers orresidues in regions 220. To aid in the removal of the nondurable layersor residues in regions 220, the conditioner/cleaner 104 can includeblowers, brushes, sponges, rollers, vacuums, and/or other cleaningelements to remove the nondurable layers of the cured overcoat materialin the regions 220. In such implementations, when the nondurable layersor residues of the overcoat material are removed, the original surfaceof the print medium 115 can be exposed for applying glue, adhesive, orother inks in subsequent processing operations of the print medium 115.

FIG. 7 depicts a flowchart of an example method 700 for generatingovercoat knockouts in printing systems that use a fixer material,printing material, and overcoat material. The method 700 can begin atbox 710 in which the printing system can apply a fixer material layer tothe surface of a print medium. In various implementations of the presentdisclosure, the fixer applicator 101 can uniformly roll or otherwiseapply a layer of fixer material across the entire surface of a printmedium. The fixer material can include any type of liquid that includeschemical, physical, and/or material properties that can interact withthe printing materials and/or the overcoat materials used in theparticular printing process.

At box 720, a print material can be selectively applied to the layer offixer material to generate corresponding printed images. In variousimplementations of the present disclosure, the fixer material can causethe smaller particles of pigment in the printing material to clusterwith one another to generate or form larger particles of pigment. Thelarger particles of pigment thus do not penetrate into or past thesurface of the print medium. When the particles of pigment remain on thesurface of the print medium, the resulting printed images can appear tobe more saturated or vibrant. In some implementations, the printingmaterial can be applied by the print engine 102 described herein.

In some example implementations, the salt of the fixer material crushesthe varnish of the overcoat material (e.g. varnish) in the non-printedareas of the print media but does not crush the overcoat in the printedareas of the print media. The mechanism in such implementations caninclude the ink that is used in the printed areas of the print mediaforming a durable solid layer that prevents the underlying salt of thefixer material from interacting with the overcoat material applied ontop of the fixer material and the printing material. In someimplementations, the fixer material layer applied to the print media caninclude one or multiple materials each formulated to interact with(e.g., crush) the printing material, the overcoat material, or both theprinting material and the overcoat material.

Once the printed image is applied on top of the fixer material on theprint medium, an overcoat material can be applied on top of the printingmaterial and the fixer material layer, at box 730. In someimplementations, the overcoat applicator 103, which can include analogand/or digital application mechanisms, can apply a coating of liquid orgel overcoat material. In regions where the overcoat material is indirect contact with the fixer material, the chemical, physical, and/ormaterial properties of the overcoat material and the fixer material canprevent the overcoat material from forming a durable coating. In suchregions, the conditioner/cleaner 104 can clean the overcoat materialfrom the surface of the print media, at box 740. Cleaning the overcoatmaterial from the regions that are in direct contact with the fixermaterial can include brushing, vacuuming, or blowing the nondurablelayer of overcoat material from the surface of the print medium 115. Theregions in which the overcoat material can be removed from the surfaceof the print medium 115 can be referred to as knockout regions.

These and other variations, modifications, additions, and improvementsmay fall within the scope of the appended claims(s). As used in thedescription herein and throughout the claims that follow, “a”, “an”, and“the” includes plural references unless the context clearly dictatesotherwise. Also, as used in the description herein and throughout theclaims that follow, the meaning of “in” includes “in” and “on” unlessthe context clearly dictates otherwise. All of the features disclosed inthis specification (including any accompanying claims, abstract anddrawings), and/or all of the elements of any method or process sodisclosed, may be combined in any combination, except combinations whereat least some of such features and/or elements are mutually exclusive.

What is claimed is:
 1. A system comprising: a fixer applicator to applya fixer material to a region of a print medium a print engine to applyselectively a printing material to sub regions of the region over thefixer material; an overcoat applicator to apply an overcoat materialover the fixer material and the print material in the region; and adryer to condition the overcoat material in direct contact with thefixer material into a nondurable layer.
 2. The system of claim 1,wherein the fixer material prevents the print material from penetratingthe print medium, and prevents the overcoat material not in the subregions from forming a durable coating.
 3. The system of claim 2,further comprising a cleaning element to remove the overcoat materialfrom the areas of the regions not in the sub region.
 4. The system ofclaim 2, wherein the nondurable layer comprises a powder.
 5. The systemof claim 1, further comprising a cleaning element to remove the overcoatmaterial from the areas of the regions not in the sub region.
 6. Thesystem of claim 5, wherein the fixer material prevents the printmaterial from penetrating the print medium, and prevents the overcoatmaterial not in the sub regions from forming a durable coating.
 7. Thesystem of claim 6, wherein the nondurable layer comprises a powder. 8.The system of claim 1, further comprising a media handler.
 9. The systemof claim 1, wherein the fixer applicator extends across a full width ofa media transport path in a direction perpendicular to the mediatransport path.
 10. The system of claim 1, wherein the overcoatapplicator extends across a full width of a media transport path in adirection perpendicular to the media transport path.
 11. The system ofclaim 5, wherein the cleaning element extends across a full width of amedia transport path in a direction perpendicular to the media transportpath.
 12. A method comprising: with a fixer applicator, applying a fixermaterial to a region of a print medium with a print engine, printingmaterial to sub regions of the region over the fixer material; and withan overcoat applicator, applying an overcoat material over the fixermaterial and the print material in the region; and with a dryer,conditioning the overcoat material in direct contact with the fixermaterial into a nondurable layer.
 13. The method of claim 12, whereinthe fixer material prevents the print material from penetrating theprint medium, and prevents the overcoat material not in the sub regionsfrom forming a durable coating.
 14. The method of claim 13, furthercomprising, with a cleaning element, removing the overcoat material fromthe areas of the regions not in the sub region.
 15. The method of claim12, wherein the nondurable layer comprises a powder.
 16. The method ofclaim 12, further comprising, with a cleaning element, removing theovercoat material from the areas of the regions not in the sub region.17. The method of claim 16, wherein the nondurable layer comprises apowder.
 18. A printing system comprising: a controller; a non-transitorycomputer readable medium comprising executable code that when executedby the controller cause the controller to control: a fixer applicator toapply a fixer material to a print medium a print engine to applyselectively a printing material to regions of the print medium over thefixer material; an overcoat applicator to apply an overcoat materialover the fixer material and the print material; and a dryer to conditionthe overcoat material in direct contact with the fixer material into anondurable layer.
 19. The printing system of claim 18, wherein the fixermaterial prevents the printing material from penetrating the printmedium, and prevents the overcoat material not in contact with theprinting material from forming a durable coating.
 20. The printingsystem of claim 18, further comprising a cleaning element to remove theovercoat material where not formed into the durable coating.